Brake-shoe key



i atented Aug. 28, 1923.

srra erg snake-S1103 KEY.

Application filed September 29, 1921. Serial No. 504,035.

T 0 aZZ whom it may concern Beit known that l, ERASTUS'EMERY, residing at Pittsburgh, in the'county of Allegheny and State of Pennsylvania, a citizen of th'eUnited States, have invented or dis covered certain new and useful Iinprove ments in' BrakeShoe Keys, of which im; provements the following-is specification.

In standard constructions the means employed for securing brake shoes to the heads in the beams consists of two spaced lugs on the head andfa lug on the backof the shoe adapted to project between the lugs'on the head; all of these lugs have openings therethrough for the reception of the locking key. The surfaces-of the lugs against which the key bears, are formed on arcs of concen-i tric circles and hence are parallel. The key, however, is made tapering from end to end and hence will have only line hearings on the surfaces of the lugs, and as has been ascertained by practice, is liable to work loose. And further, it is the practice to make the key tapering in width as well as in thick ness, and hence as. the slots in the lugs on the heads and shoes are made of the same width,-opportunity is afforded for the shoes moving laterally on the heads.

The invention described herein has for its object a construction of-key which will bear firmly entirely across the bearing faces of the lugs. It is a further object of the'in'ven tion to provide means whereby the key is looked as against accidental longitudinal movement. Theminvention is hereinafter more fully described and claimed.

Inthe accompanying drawings forming a part of this specification, Fig. 1 is a sectional elevation of. a brake shoe and brake shoe head secured together in proper relation by the improved key claimed herein; Fig. 2 is a sectional view on a plane indicated by the.

line IIII, Fig. 1; Figs. 3 and 4E and 5 are views showing different modifications in the construction of the key.

In the practice of the invention the brake shoe head and brake shoe are of standard construction. The head 1 is provided with lugs 3 and 4: having openings therethrough' for-the passage of the key and adjacent to' its upper and lower edges with abutments 5, against which the shoe will bear when in position on the head. The brake shoe 2 is provided with a lug 6 adapted to project when placed in position between the lugs 3 and 1 on the head and has an opening there through for the passageof the locking key. In the standard construction the' bearing su rfacesai on the lugs 3 and 4 and the bearingsurface b onthe lug 6, are made on arcsof concentric circles and'hence surfaces at will'be parallel with the surface bso that if a key, tapering from end to endfasin the present construction, were forced in through these lugs tolock the shoe in positio n'the key would haveonly'line hearings on the respective "lugs, The improved key 7 is formed of a thickness less than the distances between planes coincident with the: surfaces a, and the surface 5, and is so bent'or offset,

as clearlyshown at 8 in F ig. 1, that-it will bear against thesurface b for a substantial portion of the length of the surface, while portions on opposite sides of the offset will bear against the surfaces at of lugs 3 andet,

and as the key is ofv uniform thickness throughout its entire length, these portions i will bear entirely across the surfaces at andb when" the key is placed in position.-

In its preferred 'form' the key is made by bending a strip of metal preferably rectan gular in'cross section to a hairpin, shape, as-

shown, and Whenso bentthe'legs will be ap proximately parallel. and the key will have .7

such transverse dimensionsthatits legs will bear aga nst the side walls of the o 'aenings through the respectivelugs. At'its upper end the key maybe turned over to forn'ra shoulder 9 so-as to prevent itsdrOp'ping down out of position, orrthe upper end of the strip may be spread out toform a double loop forming shoulders'9 for the same pur-' pose. At its lower end the legs of the fork are bent outwardly to form shoulders 10, adapted when the key is pushed into position, to spring outwardly under the lugs 3 and thereby prevent any accidental upward movement ofthe key. the legs are bent or drawn inwardly so as to form inclined portions 11 adapted to facilitate the insertion of the key in position. It will be understood that the key is made of steel or other resilient material suitable for the purpose and the shoulders 10 are so proportioned that when the legs are pressed together, as is necessary in inserting the key,

the distance between the out-er portions of these shoulders will be less than the width of the openings through the lugs. -When the legs arepresse'd together for the insertion, the guiding portions 11' will be sub- Below the shoulders, V T

stantially narrower at their ends than the lel legs connected at one end, the width of the key being substantially equal to the transverse width of the openings through the lugs, so that the, key can be easily forced into position. It is preferred that the shoulders 10 should be inclined as shown so as to facilitate the withdrawal of the key.

As shown in Fig. 3 the portions of the legs of the key beyond the shoulders lfi'inay be'bent to form shoulders l0 adapted to bear againstxthe abutments 5 at the lower end of the head, and in that case the portions 11 of the legs may be made parallel.

The construction shown in Figs. 1 and 2 isp-reterred but the guiding-portionsll may be omitted and the ends, of the legs turned out to form the shoulders 10, as shownrin Fig. 4;, or such turned out positions may befolded back against the legs; as shown in.

I claim herein. as. my invention: v

1. A key for. connecting brake shoes to. brake. shoe heads consisting of spaced paralwidth of the slots in the lugs on the shoe and head, portions. of the legs. intermediate the ends being bent out of line with other portions of the legs, said bent out portion being so constructed as to bear on the lug on the shoe for a substantial portion of the length of the lug.

2-; A key for connecting brake shoes to brake shoe heads consisting 01" spaced paral lel legs connected at one end, the width of the key being substantially equal to the Width of the slots in the lugs on the shoe and head, portions of the legs intermediate the ends being bent out of line with other portions of the legs, said bent out portions being adapted to bear onthe lug on the shoe for a substantial portion of the length of the lug, the key provided with shoulders at both ends adapted to engage portions of the brake-shoe head to hold the key in position. 3. A key for connecting brake-shoes to brake-shoe heads, consisting of spaced parallel legs connected at one end, the width of the key being substantially equal to the width of the slots in the lugs on the shoes and heads, portions of the legs intermediate the ends being bent out of line with other portions of the legs, said bent out portions being adapted to bear on the lug on the shoe, the legs being bent outwardly adapted at both ends to form shoulders, said shoulders being approximately in the plane, of the.

1 legs and lying approximately in the plane of the legs adapted to engage portions of the head. 7 4 v 4;. A key for connecting brake-shoes tobrake-shoe-heads, consisting of spaced parallel legs'connected atone end, the'wi,dth

of the key bein substantiallyiequal to the V widths of the slots in the lugs on the shoes and heads, portions of the legs iiiterngied'nv ate the ends being'bent out of line with other portions; of the legs, said bent out portions, be 7 ing constructed to. bearon the lug of'th Shoe Y for asubstantial portion of the length of the.

lug, the ends being bent'outwardly'adjacent ito their ends to form shoulders lying approximately in the. plane; of the legsadapted to engage portions of the headand having the portions beyond the shoulders bent in wardly to guide the key when being inserted to holding position...

.5. ii key for connecting brakeshoes to. brake-shoe heads consisting of spacedpan allel legs connected atone end, thewidth of the key being equalto the widths of the slots in the lugs on the shoe andhead, the cornicetion between the legs being extended beyond the legs to form shoulders and the legs be} ing provided with shoulders adjacent, to their free ends, said shoulders being. approx;

imately inthe plane of the shoulders at the opposite ends ofthe legs.

In testimony whereof, I have hereunto set my hand.

' naasrus EM Y- I 

